Replaceable filter elements including plural filter media and related filtration systems, techniques and methods

ABSTRACT

One embodiment is a filter element including an outer filter media and an inner filter media. The outer filter media is operable to remove particulates present in a flow of fluid and/or coalesce water contained in the flow of fluid. The inner filter media is operable to remove particulates from the flow of fluid, separate water form the flow of fluid, and remove particulates from the flow of fluid. Other embodiments include unique apparatus, devices, systems, and methods relating to fuel filters and filtration. Further embodiments, forms, objects, features, advantages, aspects, and benefits of the present application shall become apparent from the detailed description and figures included herewith.

PRIORITY

The present application is a Divisional of U.S. application Ser. No.11/890,816 filed Aug. 8, 2007, which is a Continuation of InternationalApplication Number PCT/US2007/014397 the International Filing Date ofwhich is Jun. 20, 2007, which claims the benefit of priority of U.S.Application No. 60/815,118 filed Jun. 20, 2006 and U.S. Application No.60/880,145 filed Jan. 12, 2007. All of the aforementioned applicationsare hereby incorporated by reference in their entirety.

TECHNICAL FIELD

The technical field related generally to fluid filters and to methodsand systems of removing unwanted particulates and/or water from fluidwith one or more filters

BACKGROUND

Fuel injection systems for internal combustion engines, such as highpressure common rail fuel injection systems for diesel engines arevulnerable to fuel contaminants, including particulates on the order of4-6 microns and others such as larger and smaller particulates ofvarious phases and compositions which may be present in fuel. There isan unmet need to reduce or eliminate these and other fuel contaminants.

SUMMARY

One embodiment is a filter element including an outer filter media andan inner filter media. The outer filter media is operable to remove amajority of the particulates present in a flow of fluid. The innerfilter element is operable to remove finer particulates from the flow offluid that pass through the outer filter media. In addition, the outerand inner filter media comprises a multilayered filter media. Otherembodiments include unique apparatus, devices, systems, and methodsrelating to fuel filters and filtration. Further embodiments, forms,objects, features, advantages, aspects, and benefits of the presentapplication shall become apparent from the detailed description andfigures included herewith.

BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 is a side view of a vehicle including an internal combustionengine system having a fueling system.

FIG. 2 is a diagram of a representative fueling system.

FIG. 3 is a cross-sectional view of a representative filter element orcartridge.

FIG. 4 is a cross-sectional view of a representative filterincorporating the filter cartridge illustrated in FIG. 3.

FIG. 5 is a cross-sectional view of an upper portion of a representativefilter.

FIG. 6 is a perspective view of a portion of a filter cartridge.

FIG. 7 is a cross-sectional view of the upper portion of the filtercartridge illustrated in FIG. 6.

FIG. 8 is a cross-sectional view of a representative filter.

FIG. 9 is a cross-sectional view of another representative filtercartridge.

FIG. 10 is a cross-sectional view of another representative filtercartridge.

FIG. 11 is a cross-sectional view of a portion of the filter cartridgedepicted in FIG. 10.

DETAILED DESCRIPTION

For the purposes of promoting an understanding of the principles of theinvention, reference will now be made to the embodiment illustrated inthe drawings and specific language will be used to describe the same. Itwill nevertheless be understood that no limitation of the scope of theinvention is thereby intended, such alterations and furthermodifications in the illustrated device, and such further applicationsof the principles of the invention as illustrated therein beingcontemplated as would normally occur to one skilled in the art to whichthe invention relates.

With reference to FIG. 1 there is illustrated an exemplary vehicle 100including a passenger/operator cabin 102. As illustrated in FIG. 1,vehicle 100 is a semi-tractor, but could alternatively be any of avariety of other vehicles, such as a light, medium, or heavy duty truck,bus, car, sport utility vehicle, motor coach, or farm or industrialequipment, for example. In other embodiments, vehicle 100 could be amarine or aircraft vehicle. Vehicle 102 includes a fuel tank 104 andpower/propulsion 106 that includes an engine 108. Additionally, system106 includes a fueling system 110 coupled to a fuel tank 104 forproviding fuel to engine 108. A fluid conduit, pipe 112, or other flowpassage couples fuel tank 104 to fueling system 110. Engine 108 ispreferably a reciprocating piston type that is configured forcompression ignition and direct injection or port-injected dieselfueling. In other embodiments engine 108 could be another type ofengine, or power plant.

Referring to FIG. 2, fueling system 110 includes a first liquidfiltering subsystem 150, a fluid or fuel pump 152, and a second liquidfiltering subsystem 154. The first liquid filtering subsystem 150 ispositioned on the suction side of the fuel pump 152, and the secondliquid filtering subsystem 154 is positioned on the pressure side of thefuel pump 152. Filtering subsystems 150, 154 provide clean, filteredfuel that prevents pump wear, injector clogging, premature engine wearand can boost fuel efficiency. The first liquid filtering subsystem 150includes a first set of filter assemblies 156 and the second liquidfiltering subsystem 154 includes a second set of filter assemblies 158.It should be appreciated that system 110, and subsystems 150, 154 areexemplary, and that a variety of other systems and subsystems arecontemplated in various embodiments. In some embodiments, only onefilter subsystems 150, 154 having one filter in filter disclosed hereinmay be used.

The fuel tank 104 is in fluid communication with the first liquidfiltering subsystem 150. A check valve 160 is preferably positioned inthe fluid path between the fuel tank 104 and the filter assemblies 156.Check valve 160 prevents fuel from flowing back into fuel tank 104 onceit leaves fuel tank 104 and enters the first liquid filtering subsystem150. The first filtering subsystem 150 is positioned on the suction sideof the fuel pump 152. Filter assemblies 156 are capable of removingcontaminates from the fuel before they enter pump 152. The filterassemblies 156 are connected in a parallel fluid flow pathconfiguration. Although illustrated in a parallel fluid flow pathconfiguration, in alternative arrangements, the filter assemblies 156could be connected in a series flow path configuration.

Fuel that is provided to engine 108 by fuel system 110 typicallyincludes some undesirable constituents or contaminants. Suchconstituents typically include particulate matter, water, microorganismsand/or other types of contaminates. To remove these constituents, liquidfilter assemblies 150, 154 are included in the fuel system 110. As setforth in detail below, filter assemblies 156, 158 include a housing 200defining an interior space 202 for receipt of fuel and at least onefilter element 250 (See FIG. 3) positioned within interior space 202 forfiltering constituents from the fuel. Filter elements 250 disclosedherein may be used in various systems including, but not limited to,that disclosed in U.S. Pat. No. 6,939,464, which is hereby incorporatedby reference in its entirety.

At least one filter assembly 156 may include a water-in-fuel (“WIF”)sensor 162. WIF sensor 162 is positioned in a lower portion of filterassembly 156 and is used to detect water that is separated from fuel byat least one filter assembly such as assembly 156. After a predeterminedamount of water is collected by filter assembly 156, WIF sensor 162generates a signal that is sent to an engine control unit (notillustrated). The engine control unit may then generate a signal, suchas lighting a warning lamp in the cab of vehicle 100, that indicatesthat filter assembly 156 either needs to be changed, serviced, ordrained. In an alternative embodiment, filter assembly 156 automaticallydrains collected water from filter assembly 156.

The first filtering subassembly 150 also includes an electric primingand starting assist pump 164 in fluid communication with filterassemblies 156. Priming and starting assist pump 164 is positionedbetween the input to fuel pump 152 and the output of filter assemblies156. Priming and starting assist pump 164 is used to help prime andstart engine 108 by supplying fuel during engine startup. A check valve166 is in fluid communication between the input to priming and startingassist pump 164 and the output of priming and starting assist pump 164as illustrated. The check valve 166 prevents fuel from re-enteringfilter assemblies 156 through the output of filter assemblies 156 whenengine 108 is not running.

Fuel pump 152 is in fluid communication with a first and second checkvalve 168, 170. First check valve 168 can be used to release fuel backinto the suction side of fuel pump 152 if the pressure rises above apredetermined level. Second check valve 170 can be used to prevent fuelfrom leaving or exiting the second filtering subsystem 154 if engine 108is not running. Several different types of fuel pumps may be utilized indifferent embodiments. A pressure sensor 171 is located downstream ofthe output of fuel pump 152 before the input of the second filteringsubassembly 154. The pressure sensor 171 monitors the pressure of thefuel as it exits fuel pump 152 and generates a signal indicative thereofthat is sent to the engine control unit.

The output of fuel pump 152, often referred to as the pressure side, isin fluid communication with an input of the second filtering subassembly154. The second filtering subassembly 154 is preferably designed toendure higher pressures than the first filtering subassembly 150. Thefirst and second filtering subassembly 154 provides particulatefiltration and is capable of removing water from the fuel in someembodiments. The second filtering subassembly 154 may include a frameportion 172 that securely holds housings 200 of filter assemblies 158 tovehicle 102. In one form, second filtering subassembly 154 may be placedin an engine vibration isolation system 174 of the type disclosed inU.S. Provisional Patent Application Ser. No. 60/744,895, filed Apr. 14,2006, entitled Vibration Isolated Fuel Filter Head, the disclosure ofwhich is hereby incorporated by reference in its entirety. As set forththerein, the engine vibration isolation system 174 substantially reducesor eliminates vibrations that may adversely affect operation of thesecond filtering subassembly 154.

After exiting the second filtering subassembly 154, the fuel enters ahigh pressure common rail system 176 which supplies fuel to engine 108.A temperature sensor 178 is included in fluid communication with theoutlet of the second filtering subassembly 154. Temperature sensor 178is used to measure the temperature of the fuel before it enters thecommon rail system 176. A check valve 180 is included in fluidcommunication with the outlet of the second filtering subassembly 154.Check valve 180 is set to release fuel if the pressure in the fuel linerises above a predetermined level. The fuel that is released by thecheck valve is returned to fuel tank 104. Although the filters andfilter elements disclosed herein are described in connection withfiltering fuel, it should be appreciated that other types of fluid, suchas lubricants for example, could also be filtered by the filters andfilter elements.

With reference to FIG. 3, there is illustrated a representativereplaceable filter element or cartridge 250 that is housed or positionedwithin housing 200 of the first and/or second filtering subassembly 150,154 set forth in FIG. 2. Filter element 250 includes a first or outerfilter media stage 252 and a second or inner filter media stage 254radially spaced apart from outer filter media stage 252. Outer and innerfilter media stages 252, 254 extend vertically between an upper endplate 256 and a lower end plate 258. As illustrated, outer filter mediastage 252 has a vertical length longer than that of inner filter mediastage 254. In one form, outer filter media stage 252 and inner filtermedia stage 254 comprise a multi-layer filter media. Using a multi-layerfilter media improves particle filtration efficiency.

According to a preferred embodiment, an upper portion 260 of outerfilter media stage 252 is fixedly secured to a lower surface 262 ofupper end cap 256 and a lower portion 264 of outer filter media stage252 is fixedly secured to a lower surface 266 of lower end cap 258.Likewise, an upper portion 268 of inner filter media stage 254 isfixedly secured to a second lower surface 270 of upper end cap 256 and alower portion 272 of inner filter media stage 254 is fixedly secured toa second lower surface 274 of lower end cap 258. The length or height ofinner filter media stage 254 is smaller than the length or height ofouter filter media stage 252.

Outer filter media stage 252, inner filter media stage 254, upper endcap 256, and lower end cap 258 are generally cylindrical in shape, butother shapes are envisioned. Outer and inner filter media stages 252,254 may be fixed to the end caps 256, 258 in a variety of waysincluding, but not limited to, embedding, potting with adhesive, orsonic, or thermal welding. A centertube 276 may be coupled to an insidediameter 278 of inner filter media stage 254. Centertube 276 runs alongthe length of inner filter media stage 254, but could be shorter thanthe length of inner filter media stage 254. Centertube 276 includes aplurality of apertures 279 that allow fluid to flow into an inner fluidchamber 281 defined by centertube 276. An inner surface area of outerfilter media stage 252 may also be aligned or connected with a secondcentertube 277 substantially designed the same as first centertube 276.In alternative forms, centertube 276 may not be included.

Lower end cap 258 includes a lower base portion 280 and an upper baseportion 282. Lower portion 264 of outer filter media stage 252 issecured to lower base portion 280 of lower end cap 258. A lower portion272 of inner filter media stage 254 is secured to upper base portion 282of lower end cap 258. Lower base portion 280 includes an outer flange284 that protrudes upwardly from an outer edge 286 of lower end cap 258.Upper base portion 282 of lower end cap 258 includes a second outerflange 288 that also protrudes upwardly a short distance from an outeredge 290 of upper base portion 282. Second outer flange 288 keeps innerfilter media stage 254 separated from outer filter media stage 252 suchthat a gap 294 is formed between the two respective filter media stages252, 254. Lower end cap 258 may be manufactured as one piece or twopieces.

In one form, outer and inner filter media stages 252, 254 are formedusing a material that is selected to remove one or more undesirableconstituents or particulates by trapping or containing them relative tofiltered fuel downstream of such material. Further, outer and innerfilter media stages 252, 254 are preferentially formed from multiplelayers of particulate trapping material. As such, outer and inner filtermedia stages 252, 254 comprise a multi-layered filter media. In anotherform, inner and outer filter media stages 252, 254 comprise a melt blownmedia, an air-laid media, a wet-laid media, a woven media, or anon-woven media, a membrane media or a synthetic blend of one or more ofthe media types.

Outer filter media stage 252 is a multi-layered filter media stage thatis operable to remove or capture unwanted contaminates or particulatesfrom a flow of fuel. Outer filter media stage 252 may be larger orthicker than inner filter media stage 254 and is designed such that,during operation, it is responsible for capturing a majority of theunwanted particulates. In particular, in one form, outer filter mediastage 252 is designed to capture larger particulates contained in theflow of fuel. Inner filter media stage 254 is also operable to remove orcapture unwanted contaminates or particulates from the flow of fuel. Inone form, inner filter media stage 254 contains multiple layers offiltering media that are designed to remove smaller contaminates orparticulates that may not be captured or removed by outer filter mediastage 252. As such, in one form, outer filter media stage 252 removes amajority of the contaminants by capturing the larger sized particles andinner filter media stage 254 removes finer contaminates that may passthrough outer filter media stage 252.

In another form, outer filter media stage 252 comprises a coalescingfilter media operable to coalesce smaller water droplets into largerwater droplets. Outer filter media stage 252 is designed to withstandhigh pressures and to merge water droplets contained in fluid passingtherethrough by using a coalescing medium as the filter media. Thecoalescing filter media causes free water and emulsified water containedin the fuel to form into larger droplets. Outer filter media stage 252preferably utilizes the practice of liquid to liquid coalescence tomerge any water contained therein into larger water droplets. Fuel tendsto rise and water droplets fall, thereby providing clean fuel to engine108. The coalescing filter media may be based on cellulose,cellulose/glass composite, meltblown media, airlaid media, wetlaidmedia, woven media, non-woven media, membrane media or a synthetic blendof one or more of the aforementioned media types. It should beappreciated that outer filter media stage 252 and inner filter mediastage 254 also filter particulates from the flow of fuel.

Fuel introduced into filtering element 250 passes through an outersurface 253 of outer filter media stage 252. As fuel travels throughouter filter media stage 252 water droplets are combined, preferably bycoalescing, to become larger water droplets. In addition, contaminatesin the fuel are also captured by outer filter media stage 252. As thefuel and water droplets exit through an inner surface area 255 of outerfilter media stage 252, the water droplets separate from the fuel andflow downwardly toward the bottom of filter element 250. Fuel or fluidcontinues to flow to inner filter media stage 254 and the water settlesor flows downwardly to the bottom of gap 294.

In one form, the lower end plate 258 includes apertures or passages thatallow the water to flow out of filtering element 250. A gap 294 existsbetween outer filter media stage 252 and inner filter media stage 254that assists in separation of water from the fuel by allowing particlesto further coalesce, for example due to inter-particle forces andinteractions, and other forces such as gravity and interaction withother surfaces. In one form, the outer coalescing filter media 252comprises a multi-layer filter media.

In another form, inner filter media stage 254 comprises a wateradsorbing, a water separating or a water coalescing media that removes,adsorbs or separates any water droplets that may not flow to the lowersurface of gap 294 from the flow of fuel. In addition, inner filtermedia stage 254 comprises a particulate filtering media capable ofremoving particulates from the flow of fluid or fuel. As fluid passesthrough inner filter media stage 254, the water absorbing media capturesthe water droplets thereby removing them from the flow of fuel, forexample by wicking or by surface flow or by a combination or theseand/or other modes. In one form, the outer surface of filter media stage254 may be coated with or contain a water repellant or may behydrophobic, which further causes water to move through gap 294 towardthe bottom of the filtering element 250. As such, it should beappreciated that outer filter media stage 252 can cause water dropletsto be coalesced out of the fuel stream.

The water droplets move toward a lower surface of filter element 250 andthe fuel passes on through inner filter media stage 254. In anotherform, the separator may have a hydrophobic outer surface of filter mediastage 254 with at least one downstream absorbing layer, such as a layerof filter media containing a water absorbent polymer or like material.In this form, water passing through the hydrophobic outer surface offilter media stage 254 will be adsorbed by the water absorbing layer,causing it to swell and increase the restriction across the filter. Whenthe amount of water and corresponding pressure drop becomes to high,flow to the engine is restricted and the engine ceases to run, thusprotecting the engine from the detrimental effects of water. In anotherform, the in filter media 254 comprises a multi-layer filter media thatcomprises multiple layers of filtering media combined together to formwater separating media 254. In another form, the inner filter media 254comprises a multi-layer filter media that comprises multiple layers offiltering media combined together to form water separating media 254 tocapture water droplets that pass through the outer filter media stage252 and gap 294 and coalesce them into larger drops that can be removedby settling or downstream separator 254. In this case, the outer surfaceof filter media stage 254 may be hydrophobic to further cause largewater droplets to move through gap 294 toward the bottom of thefiltering element 250 and be followed by subsequent hydrophobic orhydrophilic layers to enhance coalescence.

In yet another representative form, inner filter media stage 254comprises a coalescing filter media operable to coalesce water that maypass through outer filter media stage 252 and gap 294. As such, in thisform, outer filter media stage 252 and inner filter media stage 254comprise water coalescing stages or in other words, the filter element250 includes dual coalescing stages. In other forms, outer filter mediastage 252 may include particulate removal filter media and inner filtermedia stage 254 may include coalescing filter media. The coalesced waterwill travel downwardly and the fluid or fuel will travel upwardly beforeentering fluid chamber 281. As such, clean fluid or fuel free of waterwill enter fluid chamber 281 to be used downstream. As with the previousforms, both inner and outer filter media stages 252, 254 also captureparticulates in addition to coalescing water.

All of the embodiments disclosed herein may include filter media stagesthat are operable to coalesce, adsorb water, separate water, and/orcapture particulate matter. In particular, outer and inner filter mediastages 252, 254, since they have multiple filter media layers, maycoalesce water, adsorb the coalesced water, separate water, and captureparticulates. Each layer of the filter media stages 252, 254 may bedesigned to perform different functions.

Referring to FIGS. 3 and 4, a filter 300 is depicted which includesfiltering element 250. The filter 300 includes an outer shell or housing302 that houses filtering element 250. An upper portion 304 of shell 302includes an external seal 306, a nutplate 308, and an internal seal 310.Seals 306, 310 and nutplate 308 have a generally cylindrical shape.Internal seal 310 is fixedly secured to an upper surface 312 of upperend plate 256. Internal seal 310 includes an L-shaped segment 314 thatmates with an L-shaped segment 316 of upper end plate 256.

Nutplate 308 includes an internal cylindrically threaded segment 318that protrudes upwardly from a central axis of a base portion 320.Threaded segment 318 includes an internally threaded portion 322. Anouter wing portion 324 of nutplate 308 extends upwardly and outwardlyfrom base portion 320 to an internal wall 326 of shell 302. Shell 302may comprise a permanent or disposable housing manufactured from variouscompositions. A flange 328 protrudes upwardly from an end of wingportion 324. An upper portion 330 of shell 302 wraps around an upperportion of flange 328 to secure shell 302 to flange 328 of wing portion324.

External seal 306 is connected to an outer upper edge 332 of shell 302and includes a downwardly extending segment 334 connected with an inneredge 336 of nutplate 308. The external seal 306 seals filter 300 to arespective externally threaded connector (not illustrated) in the fluidpath of fueling system 110. Inner seal 310 provides a fluid tight sealbetween end cap 256 and nutplate 308,

Wing portion 324 includes a plurality of apertures 338 that runcircumferentially around the wing portion 324. During operation, fuelenters the outer filtering media stage 252 through apertures 338. Fuelthen proceeds through the outer surface of outer filtering media stage252. Fuel then exits outer filter media stage 252 and passes into gap294 where the water droplets created by the coalescing media to movedownwardly while fuel moves upwardly. Fuel then enters inner filtermedia stage 254 where any remaining water is preferably eliminated fromthe flow of fuel.

Referring back to FIG. 3, upper end cap 256 of filter element 250includes an upper surface 340 having an inside diameter 342 and anoutside diameter 344. An outer edge 346 of upper end cap 256 includes afirst flange 348 that protrudes downwardly a predetermined distance fromouter edge 346. The flange 348 secures a portion of an outer edge 350 ofthe outer filter media stage 252 within first flange 348. An internalsegment 352 of upper end cap 256 extends downwardly from an inside edge354 of upper end cap 256 to a base portion 356, preferably to form aninternal connection chamber 358.

The internal segment 352 also includes a downwardly extending segment359 that forms a flange that is secured to outer surface 296 of innerfilter media stage 254. A second flange 360 is located at an inner edge362 of base portion 356 and extends downwardly from inner edge 362.Second flange 360 holds upper portion 268 of inner filter media stage254 in place and is connected with an inside edge 364 of inner filtermedia stage 254. Second flange 360 defines an aperture or opening thatleads to fluid chamber 281. Outer flange 348, downwardly extending 359segment 353, and internal flange 360 form U-shaped cradles the same asor similar to those illustrated in connection with lower end cap 258.The U-shaped cradles are fixedly secured to respective ends of filtermedia 252, 254 as illustrated. Although U-shaped cradles are disclosedin the preferred embodiment, the cradles may have other shapes in otherembodiments.

Referring to FIGS. 5-8, in another form, upper end cap 256 includes anouter flange 400 and an upper surface 426. Flange 400 is secured tooutside surface 401 of outer filter media stage 252. A base cap member402 having a cylindrical outer wall 404 and a base 406 are connected toan upper surface 408 of inner filter media stage 254. Base cap member402 includes an inner flange 410, and a lower portion 412 of cylindricalouter wall 404 defines an outer flange 414 that is secured to side 416of inner filter media stage 254. Inner flange 410 defines an opening 417to fluid chamber 281.

An upper cap member 418 having a downwardly extending flange 420, amid-section 422 and an upwardly extending flange 424 is connected to anupper surface 426 of upper end cap 256. Downwardly extending flange 420extends downwardly from an edge of mid-section 422 and is secured to theinside surface of an upper portion of outer wall 404 of base cap member402. Inner end cap member 418 may be connected to upper surface 426 andouter wall 404 of base cap member 402 in a variety of ways including,but not limited to, embedding, potting with adhesive, or sonic orthermal welding. A cylindrical seal 428 is fixedly secured to a lowerportion 430 of flange 420 that extends downwardly to base 406 of basecap member 402.

A nutplate 308 is connected with upper flange 424 of upper cap member418. A lower portion 434 of outer wing 324 and a lower portion 436 ofbase 320 are fixedly secured to upper cap member 418. Upwardly extendingflange 424 and base 320 may be connected with inner end cap member 418in a variety of ways including, but not limited to, embedding, pottingwith adhesive, or thermal or sonic welding. An outer edge 438 of outerwing 324 is connected with an inner surface 441 of shell 302. The outeredge 438 positions end cap 256 such that a fluid path 440 is formedbetween flange 400 and shell 302. As such, during operation, fuel entersthrough apertures 338 of nutplate 308 and travels into a fluid chamber442 where it is directed through fluid path 440 to outer filter mediastage 252,

Referring back to FIG. 4, a lower portion 380 of shell 302 includes aspring 382 that is positioned within an interior space 384 of shell 302.The spring 382 is connected with an interior surface 386 of shell 302and a lower surface 388 of lower base portion 390. The spring 382applies upward force to lower surface 388 of lower base portion 390 toforce end plate 256 against upper cap member 418, upper cap member 418against nutplate 308, and nutplate 308 against curved portion of shell302. This further helps fixedly secure all of the respective componentsor elements together.

Referring collectively to FIGS. 6 and 7, a portion of filtering element250 set forth in FIG. 5 is illustrated in further detail. Base capmember 402 is connected with upper surface 408 of inner filtering mediastage 254. Base cap member 402 includes opposing flanges 410, 414 thatextend downwardly from the outer and inner edge of base portion 406 ofbase cap member 402. Base cap member 402 also includes an upwardlyextending segment 404 that extends vertically upward from an outer edge412 of base portion 406. Flange 414 secures the outer edge of innerfiltering media stage 254 to base cap member 402. Base portion 406,outer flange 414, and inner flange 410 form a U-shaped cradle thatsecures base cap member 402 to the upper portion of inner filteringmedia stage 254.

Upwardly extending segment 404 of base cap member 402 defines acylindrical upper chamber 443. Inner flange 410 of base cap member 402defines a cylindrical lower opening 417. Base cap member 402 alsoincludes a plurality of oval shaped apertures 445 located near an upperedge 447 of upwardly extending segment 404. As set forth below, pottingmaterial or adhesive may be placed in and around apertures 445 to securebase cap member 402 to the outer edge of outer filter media stage 252.

Referring to FIG. 8, a portion of filtering element 250 set forth inFIGS. 6 and 7 is illustrated positioned within a portion of a filter550. As illustrated, an interior portion 552 of base cap member 402 hasbeen covered with a layer of potting material 554. Potting material 554creates a fluid tight seal between base cap member 402 and upper capmember 418 of filter 550. A second layer of potting material 556 may beused to seal an inner junction 556 wherein the inner end plate member418 connects with the lower surface of nutplate 324. A fluid supply tube560 is illustrated positioned through opening 417 in base cap member 402and protruding down into fluid chamber 281.

Referring to FIG. 9, another embodiment of a filtering element 250 isillustrated. Filtering element 250 includes an inner filtering mediastage 600 and an outer filtering media stage 602 radially spacedoutwardly from inner filtering media stage 600. As previously set forth,outer filter media stage 602 is formed from a material that is capableof coalescing free water and emulsified water contained in a flow offuel or fluid. Inner filter media stage 600 is formed from a waterseparating media that is capable of separating water from the flow offuel so that water does not flow downstream where it is utilized. Inaddition, outer filter media stage 602 and inner filter media stage 600are capable of removing or capturing unwanted particulates from the flowof fuel or fluid.

In other forms, inner filter media stage 600 is formed from a materialthat is capable of coalescing free water and emulsified water containedin a flow of fuel or fluid. As such, both outer filter media stage 602and inner filter media stage 600 may comprise coalescing filter media.As such, in this form, filter element 250 has two filter stages operableto coalesce water. In another representative form, outer filter mediastage 602 includes particulate filter media and inner filter media stage600 includes coalescing filter media. Inner filter media stage 600 andouter filter media stage 602 also capture unwanted particulates from theflow of fluid or fuel.

Inner filter media stage 600 extends between a first lower end cap 604and an upper end plate 606. First lower end cap 604 includes a pair ofopposing flanges 608 that extend upwardly from a base portion 610 offirst lower end cap 604. Flanges 608 and base portion 610 form aU-shaped engagement member 612 that is secured to a lower portion 614 ofinner filter media stage 600. Inner filter media stage 600 may besecured in U-shaped engagement member 612 and to a lower surface 616 ofupper end plate 606 by several attachment methods including, but notlimited to, embedding, potting with adhesive, and sonic or thermalwelding. Although U-shaped engagement members 612 are disclosed herein,it is envisioned that engagement members 612 may have other shapes inother embodiments.

Outer filter media stage 602 extends between a second lower end cap 618and upper end cap 606. Second lower end cap 618 includes a pair ofopposing flanges 620 that extend upwardly from a base portion 622 ofsecond lower end cap 618. Flanges 620 and base portion 622 form aU-shaped engagement member 624 that is secured to a lower portion 626 ofouter filter media stage 602. Outer filter media stage 602 may besecured in U-shaped engagement member 624 and to lower surface 616 ofupper end plate 606 by several attachment methods including, but notlimited to, embedding, potting with adhesive, and welding.

Outer filter media stage 602 has a length greater than that of innerfilter media stage 600. The difference in lengths forms a gap 605between a lower surface 601 of inner filter media stage 600 and a lowersurface 603 of the outer filter media stage 602. Horizontal or radialgap 652 is present between outer edge 650 of inner filter media stage600 and an inner edge 654 of outer filter media stage 602. Horizontalgap 652 allows water that has coalesced in outer filter media stage 602to travel downwardly once the water droplets formed by outer filtermedia stage 602 exits outer filter media stage 602.

Although not illustrated, filtering element 250 can be positioned in ashell 302 that includes a nutplate 324 similar to that disclosed inprevious embodiments. Lower end plate 606 includes a flange 628 thatextends upwardly from a base portion 630 of lower end plate 606. Aportion of an outer edge 632 of outer filter media stage 602 isconnected with flange 628 of lower end plate 606.

Referring to FIG. 10, a cross-sectional view of another representativefilter element 700 is illustrated. As in the previous embodiments,filter element 700 includes an inner filter media stage 702 and an outerfilter media stage 704. Outer filter media stage 704 coalesces water sothat the water forms larger water droplets and inner filter media stage702 separates out any water that remains after leaving outer filtermedia stage 704. As previously set forth, water droplets that exitfitter media stage 704 travel downwardly toward a lower surface 706 offilter element 700. Any water droplets that do not make it to lowersurface area 706 of filter element 700 enter inner filter media stage702 which removes them from the flow of fuel. In addition, inner filtermedia stage 702 and outer filter media stage 704 remove unwantedparticulates from the flow of fluid.

Filter element 700 includes an upper end plate or cap 708 and a lowerend plate or cap 710. Upper end plate 708 comprises an upper cap segment712 and a lower cap segment 714. Upper cap segment 712 is generallycylindrical in shape and includes a circular shaped male connectionmember 716 that protrudes downwardly from a lower surface 718 of uppercap segment 712. Lower cap segment 714 is also generally cylindrical inshape and has a smaller diameter than upper cap segment 712. Lower capsegment 714 includes a circular shaped female connection member 720 thatprotrudes downwardly from a lower surface 722 of lower cap segment 714.Male connection member 716 of upper cap segment 712 is fixedly securedwithin female connection member 720 of lower cap segment 714.

Upper portion 724 of inner filter media stage 702 is connected withlower surface 718 of upper cap segment 712. An upper portion 726 ofouter filter media stage 704 is connected with lower surface 722 oflower cap segment 714. Filter media stages 702, 704 may be connectedwith upper and lower cap segments 712, 714 in a variety of waysincluding, but not limited to, embedding, potting with adhesive, orsonic or thermal welding.

Lower end plate 710 may comprise a unitary piece that includes a firstU-shaped cradle 728 and a second U-shaped cradle 730. First U-shapedcradle 728 is used to secure a lower portion 732 of outer filter mediastage 704 to lower end plate 710. Second U-shaped cradle 728 is used tosecure a lower portion 734 of inner filter media stage 702 to lower endplate 710. First U-shaped cradle 728 includes an outer flange 736 thatprotrudes upwardly from a base portion 738 of lower end plate 710. Asecond flange 740 protrudes upwardly from approximately the mid-sectionof lower end plate 710. The first and second U-shaped cradles 728, 730share second flange 740. Although U-shaped cradles are disclosed herein,other shaped cradles are envisioned.

Third flange 742 protrudes upwardly from a second base portion 744 ofsecond U-shaped cradle 730. Third flange 742 forms an opening 746 inlower end plate 710 such that a fluid transfer tube 560 (for example asshown in FIG. 8) may be inserted into an interior space 748 defined byinner filter media stage 702. Seal 750 is fixedly secured to an outsideportion of third flange 742 and a lower portion 752 of second baseportion 744. Seal 750 provides a fluid tight seal between filter segment700 and fluid transfer tube 560.

Referring to FIGS. 10 and 11, to assist in water separation in fluidapplications, inner filter media stage 702 has a first length (“L1”) andouter filter media stage 704 has a second length (“L2”) which is longerthan first length L1. The difference between the first length L1 and thesecond length L2 forms a vertical gap 754 between the bottom of innerfilter media stage 702 and the bottom of outer filter media stage 704. Avariety of different gap sizes are contemplated. A horizontal space orgap 756 is provided between inner filter media stage 702 and outerfilter media stage 704. The second flange 740 of lower end plate 710 mayinclude a plurality of openings 758 that allow water to flow out of thebottom surface of filtering element 700 through lower end plate 710.

While the invention has been illustrated and described in detail in thedrawings and foregoing description, the same is to be considered asillustrative and not restrictive in character, it being understood thatonly the preferred embodiments have been shown and described and thatall changes and modifications that come within the spirit of theinventions are desired to be protected. It should be understood thatwhile the use of words such as preferable, preferably, preferred or morepreferred utilized in the description above indicate that the feature sodescribed may be more desirable, it nonetheless may not be necessary andembodiments lacking the same may be contemplated as within the scope ofthe invention, the scope being defined by the claims that follow. Inreading the claims, it is intended that when words such as “a,” “an,”“at least one,” or “at least one portion” are used there is no intentionto limit the claim to only one item unless specifically stated to thecontrary in the claim. When the language “at least a portion” and/or “aportion” is used the item can include a portion and/or the entire itemunless specifically stated to the contrary.

What is claimed is:
 1. A fuel filter, comprising: a housing for housinga filter element; the filter element including: an inner filter mediastage that defines an inner fluid chamber for filtered fuel, an outerfilter media stage spaced radially apart from the inner filter mediastage, the outer filter media stage having a vertical length longer thanthat of the inner filter media stage, an upper end cap at an upper endof the outer filter media stage, the upper end cap including an outeredge and an inside edge, wherein the outer edge includes a first flangeprotruding downwardly from the outer edge, a lower end cap structure ata lower end of the outer filter media stage, an internal segment thatextends from the upper end cap to a base portion to form an internalconnection chamber, the base portion provided at a top surface of theinner filter media stage, the internal segment including a downwardlyextending segment secured to the outside surface of the inner filtermedia stage and a second flange provided at an inner edge of the baseportion, the second flange extending downwardly from the inner edge ofthe base portion in parallel with an inside surface of the inner filtermedia stage, wherein the second flange defines an opening leading to theinner fluid chamber, wherein the inner filter media stage, the outerfilter media stage, the upper end cap, the lower end cap structure, theinternal segment and the base portion are configured to prevent fuelpassing through the outer filter media stage from bypassing the innerfilter media stage so that all of the fuel flows through and is filteredby the inner filter media stage and enters the inner fluid chamber. 2.The fuel filter of claim 1, wherein the filter element further includesa first centertube adjacent to the inside surface of the outer filtermedia stage and a second centertube adjacent on one side to the insidesurface of the inner filter media stage and adjacent on an opposite sideto the second flange.
 3. The fuel filter of claim 1, wherein the filterelement further includes an axial gap formed between the lower portionof the outer filter media stage and a lower portion of the inner filtermedia stage.
 4. A fuel filter, comprising: a housing for housing afilter element; the filter element including: an inner filter mediastage that defines an inner fluid chamber for filtered fuel, an outerfilter media stage spaced radially apart from the inner filter mediastage, the outer filter media stage having a vertical length longer thanthat of the inner filter media stage, an upper end cap at an upper endof the outer filter media stage, the upper end cap including an outeredge and an inside edge, wherein the outer edge includes a first flangeprotruding downwardly from the outer edge, an internal segment thatextends from the upper end cap to a base portion to form an internalconnection chamber, the base portion provided at a top surface of theinner filter media stage, the internal segment including a downwardlyextending segment secured to the outside surface of the inner filtermedia stage and a second flange provided at an inner edge of the baseportion, the second flange extending downwardly from the inner edge ofthe base portion in parallel with an inside surface of the inner filtermedia stage, wherein the second flange defines an opening leading to theinner fluid chamber, and an upper cap member having an upwardlyextending flange, a mid-section, and a downwardly extending flange,where the mid-section is positioned on an upper surface of the upper endcap and the downwardly extending flange is positioned adjacent theinside surface of the outer filter media stage.
 5. The fuel filter ofclaim 4, further comprising a cylindrical seal connected with a loweredge of the downwardly extending flange of the upper cap member.
 6. Thefuel filter of claim 1, further comprising a nutplate that includes acentral threaded segment that protrudes upwardly from a base portion ofthe nutplate and a wing portion that extends upwardly and outwardly awayfrom the base portion, the wing portion having a plurality of fluidpassing apertures located circumferentially around the wing portion. 7.The fuel filter of claim 6, further comprising an external sealconnected to an outer upper edge of the housing, the external sealhaving a downwardly extending segment abutting an inner edge of thenutplate.
 8. The fuel filter of claim 1, further comprising a springengaged with the filter element and positioned within an interior spaceof the housing.
 9. The fuel filter of claim 1, wherein the outer filtermedia stage is adapted to capture particulates entrained in a flow offuel, and the inner filter media stage is adapted to captureparticulates entrained in the flow of fuel.
 10. The fuel filter of claim1, wherein the housing is generally cylindrical, with an opening at oneend of the housing.
 11. The fuel filter of claim 1, wherein the lowerend cap structure includes a lower base portion secured to a lowerportion of the outer filter media stage, the lower base portion havingan outer flange that protrudes from an outer edge of the lower end cap.12. The fuel filter of claim 1, wherein the lower end cap structureincludes an upper base portion secured to a lower portion of the innerfilter media stage, the upper base portion having a second outer flangethat protrudes from an outer edge of the upper base portion.
 13. Thefuel filter of claim 1, wherein the lower end cap structure includes: afirst lower end cap positioned at a second end of the outer filter mediastage and a second lower end cap positioned at a second end of the innerfilter media stage, the first lower end cap including a lower baseportion secured to a lower portion of the outer filter media stage, thelower base portion having an outer flange that protrudes from an outeredge of the first lower end cap, and the second lower end cap includingan upper base portion secured to a lower portion of the inner filtermedia stage, the upper base portion having a second outer flange thatprotrudes from an outer edge of the upper base portion.
 14. A filterelement, comprising: an inner filter media stage that defines an innerfluid chamber for filtered fuel, an outer filter media stage spacedradially apart from the inner filter media stage, the outer filter mediastage having a vertical length longer than that of the inner filtermedia stage; an upper end cap and a lower end cap at opposing ends ofthe outer filter media stage, the upper end cap including an outer edgeand an inside edge, wherein the outer edge includes a first flangeprotruding downwardly from the outer edge; an internal segment thatextends from the upper end cap to a base portion to form an internalconnection chamber, the base portion provided at a top surface of theinner filter media stage, the internal segment including a downwardlyextending segment secured to the outside surface of the inner filtermedia stage and a second flange provided at an inner edge of the baseportion, the second flange extending downwardly from the inner edge ofthe base portion in parallel with an inside surface of the inner filtermedia stage, wherein the second flange defines an opening leading to theinner fluid chamber, wherein the inner filter media stage, the outerfilter media stage, the upper end cap, the lower end cap, the internalsegment and the base portion are configured to prevent fuel passingthrough the outer filter media stage from bypassing the inner filtermedia stage so that all of the fuel flows through and is filtered by theinner filter media stage before entering the inner fluid chamber. 15.The filter element of claim 14, further including an axial gap formedbetween a lower portion of the outer filter media stage and a lowerportion of the inner filter media stage.
 16. The filter element of claim14, further comprising a first centertube adjacent to the inside surfaceof the outer filter media stage and a second centertube adjacent on oneside to the inside surface of the inner filter media stage and adjacenton an opposite side to the second flange.